介词的基本用法与习惯搭配He came back late, ________ which time all the guests had already left
(2012·辽宁) Not until he retired from teaching three years ago __________ having a holiday abroad.
When __________ for his views about his teaching job, Philip said he found it very interesting and rewarding.
We __________ to paint the whole house but finished only the front part that day.
—When would it be __________ for you to go to the science museum with me? —I am free this Friday afternoon. Let's meet at 2 pm at the school gate.
I haven't seen Anna since she left our hometown two years ago, but we do keep in touch with each other by sending e-mails __________.